The constant stream of news about the NSA and other government agencies spying on average citizens has more people than ever before concerned about privacy and security. While no one can guarantee you'll never be hacked, the open source community has a number of applications available that can help users protect their systems.

Whether you're worried about defending your home system from malware, safeguarding a corporate network from hackers or hiding your identity from a repressive government regime, open source tools are available to help. This month, we've put together a list of 100 such tools that can replace expensive closed source software. It includes a wide variety of free anti-virus, firewall, mail gateway, data loss prevention, penetration testing, encryption, content filtering and other applications that can replace expensive software.

As always, if you'd like to call attention to an open source security app that we missed in our list, feel free to make note in the comments section below.

That article loses a lot of credibility with me when it lists Microsoft Internet Explorer as a "Popular Security Tool"

@Deo - umm...the only place IE is listed is on the line where it says a particular piece of software "replaces Internet Explorer" AFAICT.

I don't see where it calls IE a security tool...or even recommends it for anything. (Why would it possibly include it btw? IE isn't open source to begin with.)

The trick is to look at the name/title of the article. 100 Replacements for Popular Security Tools. Five of the things on that list are replacements for IE. Therefore, the article considers IE a popular security tool.